Herbicidal substituted triazolinones

ABSTRACT

Herbicidal substituted triazolinones of the formula ##STR1## in which R 1  and R 2 , independently of one another, each represents alkyl, alkenyl, alkynyl, halogenoalkyl, halogenoalkenyl, halogenoalkynyl, cyanoalkyl, alkoxyalkyl, alkoxy cycloalkyl or cycloalkylalkyl or aryl, aralkyl or heteroaryl, each of which is optionally substituted; or, together with the nitrogen atom to which they are bonded, represent an optionally substituted heterocycle, 
     R 3  and R 4 , independently of one another, each represents hydrogen, alkyl, alkenyl, alkynyl, halogenoalkyl, halogenoalkenyl, halogenoalkynyl, cyanoalkyl, hydroxyalkyl, alkoxyalkyl, alkylaminoalkyl, dialkylaminoalkyl, alkoxycarbonylalkyl or alkoxycarbonylalkenyl, cycloalkyl, cycloalkylalkyl, cycloalkenyl or cycloalkenylalkyl, each of which is optionally substituted; optionally substituted heterocyclylalkyl; aralkyl, aroyl or aryl, each of which is optionally substituted, alkoxy, alkenyloxy, alkynyloxy, aralkyloxy or aryloxy or, together with the nitrogen to which they are bonded, represent an optionally substituted heterocycle, 
     R 5  represents alkyl or cycloalkyl and 
     X represents oxygen or sulphur.

This application is a continuation of application Ser. No. 606,394,filed Oct. 31, 1990, now abandoned.

The invention relates to novel substituted triazolinones, to a pluralityof processes for their preparation and their use as herbicides.

Novel substituted triazolinones of the general formula (I) have beenfound ##STR2## in which R¹ and R², independently of one another, eachrepresents alkyl, alkenyl, alkynyl, halogenoalkyl, halogenoalkenyl,halogenoalkynyl, cyanoalkyl, alkoxyalkyl, alkoxy, cycloalkyl,cycloalkylalkyl, aryl, aralkyl or heteroaryl, each of which isoptionally substituted, or, together with the nitrogen atom to whichthey are bonded, represent an optionally substituted heterocycle,

R³ and R⁴, independently of one another, each represents hydrogen,alkyl, alkenyl, alkynyl, halogenoalkyl, halogenoalkenyl,halogenoalkynyl, cyanoalkyl, hydroxyalkyl, alkoxyalkyl, alkylaminoalkyl,dialkylaminoalkyl, alkoxycarbonylalkyl oralkoxycarbonylalkenyl;cycloalkyl, cycloalkylalkyl, cycloalkenyl or cycloalkenylalkyl, each ofwhich is optionally substituted ; optionally substitutedheterocyclylalkyl; aralkyl, aroyl or aryl, each of which is optionallysubstituted, alkoxy, alkenyloxy, alkynyloxy, aralkyloxy or aryloxy, or,together with the nitrogen to which they are bonded, represent anoptionally substituted heterocycle,

R⁵ represents alkyl or cycloalkyl and

X represents oxygen or sulphur.

Furthermore, it has been found that the novel substituted triazolinonesof the general formula (I).are obtained if

a) triazolinones of the general formula (II) ##STR3## in which R¹, R²and R⁵ have the meanings given above,

and/or tautomers of these compounds, i.e. the correspondinghydroxytriazoles are reacted, optionally in the presence of a reactionauxiliary and optionally in the presence of a diluent, withiso(thio)cyanates of the general formula (III)

    R.sup.4 -N=C=X                                             (III)

in which

R⁴ and X have the meanings given above,

° or if

b) chlorocarbonyl-triazolinones of the general formula (IV) ##STR4## inwhich R¹, R² and R⁵ have the meanings given above,

are reacted, optionally in the presence of an acid-binder and optionallyin the presence of a diluent, with amines of the general formula (V)##STR5## in which R³ and R⁴ have the meanings given above.

Finally, it has been found that the novel substituted triazolinones ofthe general formula (I) have interesting herbicidal properties.

In the general formulae, halogen denotes fluorine, chlorine, bromine andiodine, preferably fluorine, chlorine or bromine, in particular fluorineor chlorine.

Optionally substituted aryl groups such as, for example, aryl, aralkyland aryloxy can carry one or more, preferably 1 to 5, in particular 1 to3, and particularly preferably 1 or 2, identical or differentsubstituents.

In aryl-containing radicals, aryl preferably represents phenyl ornaphthyl.

The radicals R¹ and R², or R³ and R⁴, in the event that they form aheterocycle together with the nitrogen atom to which they are bonded,preferably represent a heterocycle which is optionally mono-, di- ortri-substituted by identical or different substituents, and has theformula ##STR6## the selected substituents being: halogen, and alkyl orhalogenoalkyl, each of which is straight-chain or branched, and eachhaving 1 to 4 carbon atoms and, if appropriate, 1 to 9, preferably 1 to5, in particular 1 to 3, identical or different halogen atoms Particularpreference is given to the substituents methyl, ethyl, n- or i-propyl,chlorine and trifluoromethyl.

The heterocyclyl moiety in the meaning of heterocyclylalkyl for R³ andR⁴ preferably represents the following heterocycles: ##STR7## Zrepresenting oxygen or sulphur in each case.

Alkyl in the meaning of heterocyclylalkyl represents for example methyl,ethyl, n- or iso-propyl, n-, iso-, sec- or tert-butyl.

The heterocycle in the meaning of heterocyclylalkyl can be mono- orpoly-substituted, preferably monoto tri-substituted, in particular mono-or di-substituted by identical or different alkyl or halogenoalkylradicals, each of which may be straight-chain or branched, having 1 to4, preferably 1 or 2 carbon atoms and 1 to 9, preferably 1 to 5, inparticular 1 to 3, identical or different halogen atoms or by alkanediylor alkenediyl, each of which is doubly linked, having up to 4 carbonatoms. In particular, the substituents selected are methyl and ethyl.

Preference is given to compounds of the formula (I) in which

R¹ and R², independently of one another, represent alkyl having 1 to 8carbon atoms, alkenyl having 2 to 8 carbon atoms, alkyl having 2 to 8carbon atoms, halogenoalkyl having 1 to 8 carbon atoms and 1 to 17identical or different halogen atoms, halogenoalkenyl or halogenoalkynyleach having 2 to 8 carbon atoms and 1 to 15 or 13 identical or differenthalogen atoms respectively, cyanoalkyl, alkoxyalkyl or alkoxy, eachhaving 1 to 6 carbon atoms in the individual alkyl moieties, each of thepreceding species being straight-chain or branched, represent cycloalkylhaving 3 to 7 carbon atoms, represent cycloalkylalkyl having 3 to 7carbon atoms in the cycloalkyl moiety and 1 to 6 carbon atoms in thealkyl moiety or represent aralkyl having 6 to 10 carbon atoms in thearyl moiety and 1 to 6 carbon atoms in the alkyl moiety, aryl having 6to 10 carbon atoms or heteroaryl having 2 to 9 carbon atoms and 1 to 3hetero atoms, in particular nitrogen, oxygen and/or sulphur, each ofthese species being optionally monoor poly-substituted by identical ordifferent substituents, suitable substituents in each case being:halogen, cyano, nitro and also alkyl, alkoxy, alkylthio, halogenoalkyl,halogenoalkoxy or halogenoalkylthio, each of which may be straight-chainor branched, each having 1 to 4 carbon atoms and, if appropriate, 1 to 9identical or different halogen atoms or

R¹ and R², together with the nitrogen atom to which they are bonded,represent a 5- to 10-membered heterocycle which is optionally mono- orpoly-substituted by identical or different substituents and mayoptionally contain 1 to 2 other hetero atoms, in particular nitrogen,oxygen and/or sulphur, suitable substituents being: halogen and alsoalkyl or halogenoalkyl, each of which may be straight-chain or branched,each having 1 to 4 carbon atoms and if appropriate, 1 to 9 identical ordifferent halogen atoms and also 1 to 2 oxo or thioxo groups,

R³ and R⁴, independently of one another, represent hydrogen, representalkyl having 1 to 18 carbon atoms, alkenyl having 2 to 8 carbon atoms,alkynyl having 2 to 8 carbon atoms, halogenoalkyl having 1 to 8 carbonatoms and 1 to 17 identical or different halogen atoms, halogenoalkenylor halogenoalkynyl, each having 2 to 8 carbon atoms and 1 to 15 or 13identical or different halogen atoms respectively, cyanoalkyl having 1to 8 carbon atoms, hydroxyalkyl having 1 to 8 carbon atoms and 1 to 6hydroxyl groups, alkoxyalkyl, alkoxycarbonylalkyl oralkoxycarbonylalkenyl, each having up to 6 carbon atoms in theindividual alkyl or alkenyl moieties, alkylaminoalkyl ordialkylaminoalkyl, each having 1 to 6 carbon atoms in the individualalkyl moieties, each of these species being straight-chain or branched,or represent cycloalkyl, cycloalkylalkyl, cycloalkenyl orcycloalkenylalkyl, each having 3 to 8 carbon atoms in the cycloalkyl orcycloalkenyl moiety and, if appropriate, 1 to 6 carbon atoms in thealkyl moiety, each of which is optionally mono-or poly-substituted byidentical or different substituents, suitable substituents in each casebeing: halogen, cyano and also alkyl or halogenoalkyl, each of which maybe straight-chain or branched, each having 1 to 4 carbon atoms and, ifappropriate, 1 to 9 identical or different halogen atoms or alkanediylor alkenediyl, each of which is doubly linked, each having up to 4carbon atoms; furthermore R³ and R⁴, independently of one anotherrepresent heterocyclylalkyl having 1 to 6 carbon atoms in thestraight-chain or branched alkyl moiety and 1 to 9 carbon atoms and 1 to3 hetero atoms in the heterocyclyl moiety, in particular nitrogen,oxygen, and/or sulphur, the heterocyclyl moiety being optionally mono-or poly-substituted by identical or different substituents, suitablesubstituents being: halogen, cyano, nitro and also alkyl, alkoxy,alkylthio, halogenoalkyl, halogenoalkoxy, halogenoalkylthio oralkoxycarbonyl, each of which is straight-chain or branched, each having1 to 5 carbon atoms and, if appropriate, 1 to 9 identical or differenthalogen atoms; furthermore, R³ and R⁴, independently of one another,represent alkoxy having 1 to 8 carbon atoms, alkenyloxy having to 8carbon atoms or alkynyloxy having 2 to 8 carbon atoms, each beingstraight-chain or branched, or represent aralkyl, aralkyloxy, aryloxy ,aroyl or aryl, each having 6 to 10 carbon atoms in the aryl moiety and,if appropriate, 1 to 6 carbon atoms in the alkyl moiety, each of whichis optionally mono-or poly-substituted by identical or differentsubstituents, suitable aryl substituents in each case being: halogen,cyano, nitro, hydroxyl and also alkyl, alkoxy, alkylthio, halogenoalkyl,halogenoalkoxy, halogenoalkylthio, alkylsulphinyl, alkylsulphonyl,halogenoalkylsulphinyl, halogenoalkylsulphonyl, alkanoyl oralkoxycarbonyl, each of which may be straight-chain or branched, eachhaving 1 to 6 carbon atoms and, if appropriate, 1 to 9 identical ordifferent halogen atoms, cycloalkyl having 3 to 6 carbon atoms orphenoxy and suitable alkyl substituents, if desired, being: halogen orcyano, or

R³ and R⁴, together with the nitrogen atom to which they are bonded,represent a 5- to 10-membered heterocycle which is optionally mono- orpoly-substituted by identical or different substituents and optionallycontains 1 to 2 other hetero atoms, in particular nitrogen, oxygenand/or sulphur, suitable substituents being: halogen and also alkyl orhalogenoalkyl, each of which may be straight-chain or branched, eachhaving 1 to 4 carbon atoms and, if appropriate, 1 to 9 identical ordifferent halogen atoms, and also 1 to 2 oxo or thioxo groups,

R⁵ represents straight-chain or branched alkyl having 1 to 8 carbonatoms or cycloalkyl having 3 to 8 carbon atoms and

X represents oxygen or sulphur.

Particular preference is given to the compounds of the formula (I) inwhich

R¹ and R², independently of one another, each represents methyl, ethyl,n- or i-propyl, n-, i-, s- or t-butyl, n- or i-pentyl, allyl, propargyl,represents halogenoalkyl having 1 to 4 carbon atoms, halogenoalkenylhaving 3 to 6 carbon atoms or halogenoalkinyl having 3 to 6 carbonatoms, and in each case having 1 to 9 identical or different halogenatoms, each of these species being straight-chain or branched,represents cyanoethyl, methoxyethyl, methoxyethyl, dimethoxyethyl,methoxy, ethoxy, represents cyclopropyl, cyclopropylmethyl, cyclopentyl,cyclohexyl, cyclohexylmethyl, cyclohexylethyl, cyclopentylmethyl orrepresents benzyl, phenylethyl or phenyl, each of which is optionallymono- to tri-substituted by identical or different substituents,suitable substituents being: fluorine, chlorine, bromine, cyano, nitro,methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl, methoxy, ethoxy,methylthio, trifluoromethyl, trifluoromethoxy or trifluoromethylthio or

R¹ and R², together with the nitrogen atom to which they are bonded,represent a heterocycle of the formula ##STR8## which is optionallymono- to tri-substituted by identical or different substituents,suitable substituents being: methyl, ethyl, n- or i-propyl, chloro ortrifluoromethyl,

R³ represents hydrogen or methyl,

R⁴ represents methyl, ethyl, n- or i-propyl, n-, i-, s-or t-butyl,represents pentyl, hexyl, heptyl, octyl, nonyl, decyl or dodecyl, eachof which is straight-chain or branched, represents allyl, representsbutenyl, pentenyl, hexenyl, propargyl, butynyl, pentynyl or hexynyl,each of which is straight-chain or branched, represents straight-chainor branched halogenoalkyl having 1 to 6 carbon atoms and 1 to 9identical or different halogen atoms, in particular fluorine, chlorineor bromine, represents halogenoalkenyl or halogenoalkynyl, each of whichis straight-chain or branched, each having 3 to 5 carbon atoms and 1 to3 halogen atoms, in particular fluorine or chlorine, representscyanoalkyl having 1 to 6 carbon atoms in the alkyl moiety, hydroxyalkylhaving 1 to 6 carbon atoms and 1 to 3 hydroxyl groups, alkoxyalkyl,alkoxycarbonylalkyl or alkoxycarbonylalkenyl, alkylaminoalkyl ordialkylaminoalkyl, each of which is straight-chain or branched, eachhaving up to 4 carbon atoms in the individual alkyl and alkenylmoieties, or represents cyclopropyl, cyclopropylmethyl,cyclopropylethyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl,cyclohexylmethyl, cyclohexylethyl, cyclohexenyl or cyclohexenylmethyl,each of which is optionally mono- to tri-substituted by identical ordifferent substituents, suitable substituents in each case being:fluorine, chlorine, bromine, methyl, ethyl, n- or i-propyl, n-, i-, s-or t-butyl, cyano, methanediyl, ethanediyl, butanediyl or butadienediyl;furthermore represents heterocyclylmethyl, heterocyclylpropyl orheterocyclylethyl, each of which is optionally mono- to tri-substitutedby identical or different substituents in the heterocyclyl moiety,suitable heterocycles in each case being: ##STR9## Z in each caserepresenting oxygen or sulphur and suitable substituents being:fluorine, chlorine, bromine, cyano, nitro, methyl, ethyl, n- ori-propyl, n-, i-, s- or t-butyl, methoxy, ethoxy, methylthio,trifluoromethyl, trifluoromethoxy or trifluoromethylthio; R⁴ furthermorerepresents alkoxy having 1 to 6 carbon atoms, alkenyloxy having 3 to 6carbon atoms or alkynyloxy having 3 to 6 carbon atoms, each of which isstraight-chain or branched, or represents benzyl, phenylethyl,phenylpropyl, phenylbutyl, phenylpentyl, phenylhexyl, phenylheptyl,phenylcyanomethyl, phenylcyanoethyl, phenylcyanopropyl, benzyloxy,phenylethyloxy, phenoxy, benzoyl, phenyl or naphthyl, each of which isoptionally straight-chain or branched and optionally mono- totri-substituted by identical or different substituents, suitable phenylsubstituents in each case being: fluorine, chlorine, bromine, hydroxyl,cyano, nitro, methyl, ethyl, n- or i-propyl, n-, i-, s- or t-butyl,methoxy, ethoxy, methylthio, trifluoromethyl, trifluoromethoxy,trifluoromethylthio, trifluoromethylsulphinyl, trifluoromethylsulphonyl,methylsulphinyl, methylsulphonyl, acetyl, propionyl, methoxycarbonyl,ethoxycarbonyl, cyclohexyl or phenoxy; or

R³ and R⁴, together with the nitrogen atom to which they are bonded,represent a heterocycle of the formula ##STR10## which is optionallymono- to tri-substituted by identical or different substituents,suitable substituents being: methyl, ethyl, n- or i-propyl, chlorine ortrifluoromethyl,

R⁵ represents methyl, ethyl, propyl, isopropyl, n-, i-, s- or t-butyl,cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl and

X represents oxygen or sulphur.

Most particular preference is given to the compounds of the formula (I)in which

R¹ represents methyl, ethyl, n- or i-propyl, n-, i-, s-or t-butyl, n- ori-pentyl, cyclopropyl, cyclopentyl or cyclohexyl,

R² represents methyl, ethyl, n- or i-propyl, n-, i-, s-or t-butyl, n- ori-pentyl or

R¹ and R², together with the nitrogen atom to which they are bonded,represent a heterocycle of the formula ##STR11## R³ represents hydrogen,R⁴ represents methyl, ethyl, n- or i-propyl,, n-, i-, s-or t-butyl,allyl, propargyl, represents pentyl, hexyl, heptyl, butenyl, pentenyl,butynyl, pentynyl or hexynyl, each of which is straight-chain orbranched, halogenoalkyl having 1 to 5 carbon atoms and 1 to 9 identicalor different halogen atoms, in particular fluorine or chlorine,cyclopropyl, cyclopentyl or cyclohexyl, each of which is optionallymono-, di- or tri-substituted by identical or different substituentsfrom the series comprising methyl, ethyl, fluorine or chlorine,represents phenyl, benzyl or phenylethyl, each of which is optionallymono-, di- or tri-substituted, in particular monosubstituted, byidentical or different substituents, the substituents chosen beingfluorine, chlorine, methyl, ethyl, methoxy, ethoxy, methylthio,trifluoromethoxy and trifluoromethylthio, and benzyl or phenylethyl, inparticular, being unsubstituted,

R⁵ represents methyl, ethyl, n- or i-propyl, in particular methyl, and

X represents oxygen.

If, for example, the starting materials used are5-dimethylamino-1-methyl-1,2-dihydro-3H-1,2,4-triazol-3-one andtert-butyl isocyanate, the course of the reaction of the process (a)according to the invention can be represented by the following reactionscheme: ##STR12##

If, for example the starting materials used are2-chlorocarbonyl-1-methyl-5-piperidino-1,2-dihydro-3H-1,2,4-triazol-3-oneand diethylamine, the course of the reaction of the process (b)according to the invention can be represented by the following reactionscheme: ##STR13##

The radicals (R¹, R², X, etc.) which are defined in the active compoundsof the formula (I) also have the meanings given in the compounds of theformula (I) in all definition contexts of the intermediates andprecursors. This is also the case for the radicals which are repeatedlymentioned in the precursors and intermediates.

The starting materials of the formula (II) or the hydroxytriazolestautomeric thereto are known and/or can be prepared by processes whichare known per se (cf. DE-A-2,042,660, DE-A-2,330,089, DE-A-2,428,204 andDE-A-2,537,973).

For example, the triazolinones of the formula (II) are obtained ifcyanamides of the formula (VI) ##STR14## in which R¹ and R² have themeanings given above,

are reacted at temperatures of between 20° C. and 150° C. withchloroformic esters of the formula (VII)

    Cl--COOR                                                   (VII)

in which

R represents methyl, ethyl or phenyl, preferably phenyl,

and the resulting chloroformamidine derivatives of the formula (VIII)##STR15## in which R, R¹ and R² have the meanings given above,

are reacted at temperatures of between 0° C. and 100° C., optionallyafter isolation by vacuum distillation or by other customary methods,with alkyl hydrazines of the formula (IX)

    R.sup.5 --NH--NH.sub.2                                     (IX)

in which

R⁵ has the meaning given above,

optionally in the presence of diluents such as, for example, methylenechloride, dioxane and/or diethyl ether, and the product is worked up bycustomary methods (cf. the preparative examples).

The starting materials of the formula (III) are known organic synthesischemicals.

The starting materials of the formula (IV) are not yet known from theliterature.

The novel chlorocarbonyl-triazolinones of the formula (IV) are obtainedif triazolinones of the formula (II) ##STR16## in which R¹, R² and R⁵have the meanings given above,

are reacted at temperatures of between 0° C. and 150° C. with phosgene,optionally in the presence of an acid-binder such as, for example,triethylamine, and optionally in the presence of a diluent such as, forexample, toluene or acetonitrile.

The starting materials of the formula (V) are known organic synthesischemicals.

The process (a) according to the invention for the preparation of thenovel substituted triazolinones of the formula (I) is preferably carriedout with the use of diluents. Suitable diluents for this purpose arevirtually all inorganic solvents. These include, preferably, aliphaticand aromatic, optionally halogenated hydrocarbons, such as pentane,hexane, heptane, cyclohexane, petroleum ether, naphtha, ligroin,benzene, toluene, xylene, methylene chloride, ethylene chloride,chloroform, carbon tetrachloride, chlorobenzene and o-dichlorobenzene,ethers such as diethyl and dibutyl ether, glycol dimethyl ether anddiglycol dimethyl ether, tetrahydrofuran and dioxane, ketones such asacetone, methyl ethyl ketone, methyl isopropyl ketone and methylisobutyl ketone, esters such as methyl acetate and ethyl acetate,nitriles such as, for example, acetonitrile and propionitrile, amidessuch as, for example, dimethylformamide, dimethylacetamide andN-methyl-pyrrolidone and also dimethyl sulphoxide, tetramethylenesulphone and hexamethyl phosphoric triamide.

The process (a) according to the invention can optionally be carried outin the presence of a basic reaction auxiliary. Suitable reactionauxiliaries include all the customary inorganic and organic bases.Preference is given to the use of tertiary amines such as triethylamine,N,N-dimethylaniline, pyridine, N,N-dimethylaminopyridine,diazabicyclooctane (DABCO), diazabicyclononene (DBN) ordiazabicycloundecene (DBU).

However, the addition of catalysts of this type is not absolutelynecessary.

The reaction temperatures for carrying out the process (a) according tothe invention can be varied within wide limits. Operating temperaturesof between 0° C. and +150° C., preferably temperatures of between +40°C. and +120° C. are selected.

The process (a) according to the invention is normally carried out underatmospheric pressure. However, it is also possible, in particular withgaseous starting compounds, to operate under elevated pressure.

The process (a) according to the invention is carried out using, permole of triazolinone of the formula (II), generally 1 to 5 moles,preferably 1 to 2.5 mole of iso(thio)cyanate of the formula (III) andoptionally 1 to 2.5 mole of reaction auxiliary. Carrying out thereaction, working up and isolating the reaction products takes placeanalogously to generally known processes (cf. the preparative examples).

Inert organic solvents are likewise suitable as diluents for carryingout the process (b) according to the invention. Preference is given tothe use of the diluents mentioned in process (a).

The process (b) according to the invention is optionally carried out inthe presence of a suitable acid-binder. Suitable acid-binders includeall customary inorganic or organic bases. These include, for example,alkali metal hydroxides such as sodium hydroxide or potassium hydroxide,alkali metal carbonates such as sodium carbonate, potassium carbonate orsodium hydrogen carbonate, and also tertiary amines such astriethylamine, N,N-dimethylaniline, pyridine, N,N-dimethylaminopyridine,diazabicyclooctane (DABCO), diazabicyclononene (DBN) ordiazabicycloundecene (DBU).

It is also possible to use the amine of the

(V), employed as a reactant, simultaneously in suitable excess as theacid-binder.

The reaction temperatures used for carrying out the process (b)according to the invention can be varied within wide limits. Generally,operating temperatures of between 0° C. and +150° C., preferablytemperatures of between +10° C. and +80° C., are selected.

The process (b) according to the invention is normally carried out underatmospheric pressure. However, it is also possible to operate underelevated pressure

The process (b) according to the invention is carried out using, permole of chlorocarbonyl-triazolinone of the formula (IV), generally 1 to5 moles, preferably 1 to 2.5 moles of the amine of the formula (V) andoptionally 1 to 2.5moles of acid-binder. Carrying out the reaction,working up and isolating the reaction products takes place analogouslyto generally known processes (cf. the preparative examples).

The active compounds according to the invention can be used asdefoliants, desiccants, agents for destroying broad-leaved plants and,especially, as weedkillers. By weeds, in the broadest sense, there areto be understood all plants which grow in locations where they areundesired. Whether the substances according to the invention act astotal or selective herbicides depends essentially on the amount used.

The active compounds according to the invention can be used, forexample, in connection with the following plants:

Dicotyledon weeds of the genera: Sinapis, Lepidium, Galium, Stellaria,Matricaria, Anthemis, Galinsoga, Chenopodium, Urtica, Senecio,Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum,Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa, Rotala,Lindernia, Lamium, Veronica, Abutilon, Emex, Datura, Viola, Galeopsis,Papaver and Centaurea.

Dicotyledon cultures of the genera: Gossypium, Glycine, Beta, Daucus,Phaseolus, Pisum, Solanum, Linum, Ipomoea, Vicia, Nicotiana,Lycopersicon, Arachis, Brassica, Lactuca, Cucumis and Cucurbita.

Monocotyledon weeds of the genera: Echinochloa, Setaria, Panicum,Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus,Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis,Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea,Dactyloctenium, Agrostis, AIopecurus and Apera.

Monocotyledon cultures of the genera: Oryza, Zea, Triticum, Hordeum,Avena, Secale, Sorghum, Panicum, Saccharum, Ananas, Asparagus andAllium.

However, the use of the active compounds according to the invention isin no way restricted to these genera, but also extends in the samemanner to other plants.

The compounds are suitable, depending on the concentration, for thetotal combating of weeds, for example on industrial terrain and railtracks, and on paths and squares with or without tree plantings.Equally, the compounds can be employed for combating weeds in perennialcultures, for example afforestations, decorative tree plantings,orchards, vineyards, citrus groves, nut orchards, banana plantations,coffee plantations, tea plantations, rubber plantations, oil palmplantations, cocoa plantations, soft fruit plantings and hopfields, andfor the selective combating of weeds in annual cultures.

The compounds according to the invention of the formula (I) are alsosuitable, in particular, for the selective combating of dicotyledonweeds in monocotyledon crops by the preemergence and postemergencemethods, in particular by the postemergence method.

Within certain limits, the compounds of the formula (I) also exhibitdefoliant action in cotton, action against Pyricularia oryzae and/oralso leaf insecticidal and acaricidal action.

The active compounds can be converted into the customary formulations,such as solutions, emulsions, wettable powders, suspensions, powders,dusting agents, pastes, soluble powders, granules, suspension-emulsionconcentrates, natural and synthetic materials impregnated with activecompound, and very fine capsules in polymeric substances.

These formulations are produced in a known manner, for example by mixingthe active compounds with extenders, that is liquid solvents and/orsolid carriers, optionally with the use of surface-active agents, thatis emulsifying agents and/or dispersing agents and/or foam-formingagents.

In the case of the use of water as an extender, organic solvents can,for example, also be used as auxiliary solvents. As liquid solvents,there are suitable in the main: aromatics, such as xylene, toluene oralkylnaphthalenes, chlorinated aromatics and chlorinated aliphatichydrocarbons, such as chlorobenzenes, chloroethylenes or methylenechloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, forexample petroleum fractions, mineral and vegetable oils, alcohols, suchas butanol or glycol as well as their ethers and esters, ketones, suchas acetone, methyl ethyl ketone, methyl isobutyl ketone orcyclohexanone, strongly polar solvents, such as dimethylformamide anddimethyl sulphoxide, as well as water.

As solid carriers there are suitable: for example ammonium salts andground natural minerals, such as kaolins, clays, talc, chalk, quartz,attapulgite, montmorillonite or diatomaceous earth, and ground syntheticminerals, such as highly disperse silica, alumina and silicates, assolid carriers for granules there are suitable: for example crushed andfractionated natural rocks such as calcite, marble, pumice, sepioliteand dolomite, as well as synthetic granules of inorganic and organicmeals, and granules of organic material such as sawdust, coconut shells,corn cobs and tobacco stalks; as emulsifying and/or foamforming agentsthere are suitable: for example non-ionic and anionic emulsifiers, suchas polyoxyethylene fatty acid esters, polyoxyethylene fatty alcoholethers, for example alkylaryl polyglycol ethers, alkylsulphonates, alkylsulphates, arylsulphonates as well as albumin hydrolysis products; asdispersing agents there are suitable: for example ligninsulphite wasteliquors and methylcellulose.

Adhesives such as carboxymethylcellulose and natural and syntheticpolymers in the form of powders, granules or latexes, such as gumarabic, polyvinyl alcohol and polyvinyl acetate, as well as naturalphospholipids, such as cephalins and lecithins, and syntheticphospholipids, can be used in the formulations. Further additives can bemineral and vegetable oils.

It is possible to use colorants such as inorganic pigments, for exampleiron oxide, titanium oxide and Prussian Blue, and organic dyestuffs,such as alizarin dyestuffs, azo dyestuffs and metal phthalocyaninedyestuffs, and trace nutrients such as salts of iron, manganese, boron,copper, cobalt, molybdenum and zinc.

The formulations in general contain between 0.1 and 95 per cent byweight of active compound, preferably between 0.5 and 90%.

For combating weeds, the active compounds according to the invention, assuch or in the form of their formulations, can also be used as mixtureswith known herbicides, finished formulations or tank mixes beingpossible.

Suitable herbicides for the mixtures are known herbicides, such as, forexample,1-amino-6-ethylthio-3-(2,2-dimethylpropyl)-1,3,5-triazine-2,4(lH,3H)-dione(AMETHYDIONE) or N-(2-benzothiazolyl)-N,N'-dimethylurea(METABENZTHIAZURON) for combating weeds in cereals;4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4H)-one (METAMITRON) forcombating weeds in sugar beets, and4-amino-6-(1,1-dimethylethyl)-3-methylthio-1,2,4-triazin 5(4H)-one(METRIBUZIN) for combating weeds in soy beans; Furthermore also2,4-dichlorophenoxyacetic acid (2,4-D); 4-(2,4-dichlorophenoxy)butyricacid (2,4-DB); 2,4-di-chlorophenoxypropionic acid (2,4-DP);N-(methoxymethyl)-2,6-diethylchloroacetanilide (ALACHLOR);2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine(ATRAZINE);3-isopropyl-2,1,3-benzothiadiazin-4-one-2,2-dioxide(BENTAZONE); methyl 5-(2,4-dichlorophenoxy)-2-nitrobenzoate (BIFENOX);3,5-dibromo-4-hydroxy-benzonitrile (BROMOXYNIL);2-chloro-N-{[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-amino]-carbonyl}benzenesulphonamide(CHLORSULFURON); N,N-dimethyl-N,-(3-chloro-4-methylphenyl)-urea(CHLORTOLURON);2-chloro-4-ethylamino-6-(3-cyanopropylamino)-1,3,5-triazine (CYANAZINE);2-[4-(2,4-dichlorophenoxy)-phenoxy]-propionic acid, its methyl ester orits ethyl ester (DICLOFOP) S-ethyl N,N-di-n-propyl-thiocarbamate(EPTAME);4-amino-6-t-butyl-3-ethylthio-1,2,4-triazin-5(4H)-one(ETHIOZIN);2-{4-[(6-chloro-2-benzoxazolyl)-oxy]-phenoxy}-propanoic acid,its methyl ester or its ethyl ester (FENOXAPROP);[(4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)-oxy]-acetic acid or its1-methylheptyl ester (FLUROXYPYR); methyl2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-lH-imidazol-2-yl]-4(5)-methylbenzoate(IMAZAMETHABENZ); 3,5-diiodo-4-hydroxybenzonitrile (IOXYNIL);N,N-dimethyl-N'-(4-isopropylphenyl)-urea (ISOPROTURON);(2-methyl-4-chlorophenoxy)acetic acid (MCPA);(4-chloro-2-methylphenoxy)-propionic acid (MCPP);N-methyl-2-(1,3-benzothiazol-2-yloxy)-acetanilide (MEFENACET);2-chloro-N-(2,6-dimethylphenyl)-N-[(lH)-pyrazol-1-yl-methyl]-acetamide(METAZACHLOR);2-ethyl-6-methyl-N-(1-methyl-2-methoxyethyl)-chloroacetanilide(METOLACHLOR);2{[[((4-methoxy-6-methyl-1,3,5-triazin-2-yl)-amino)-carbonyl]-amino]-sulphonyl}-benzoicacid or its methyl ester (METSULFURON);N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitro-aniline (PENDIMETHALIN);O-(6-chloro-3-phenyl-pyridazin-4-yl) S-octyl thiocarbonate carbonate(PYRIDATE); 4-ethylamino-2-t-butylamino-6-methylthio-s-triazine(TERBUTRYNE); methyl3-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-amino]-carbonyl]-amino]-sulphonyl]-thiophene2-carboxylate(THIAMETURON): andN,N-diisopropyl-S-(2,3,3-trichloroallyl)-thiolcarbamate (TRIALLATE)Surprisingly, some mixtures also show synergistic action.

Mixtures with other known active compounds, such as fungicides,insecticides, acaricides, nematicides, bird repellents plant nutrientsand agents which improve soil structure, are also possible.

The active compounds can be used as such, in the form of theirformulations or in the use forms prepared therefrom by further dilution,such as ready-to-use solutions, suspensions, emulsions, powders, pastesand granules. They are used in the customary manner, for example bywatering, spraying, atomizing or scattering.

The active compounds according to the invention can be applied eitherbefore or after emergence of the plants. They can also be incorporatedinto the soil before sowing.

The amount of active compound used can vary within a substantial range.It depends essentially on the nature of the desired effect. In general,the amounts used are between 0.01 and 10 kg of active compound perhectare of soil surface, preferably between 0.05 and 5 kg per ha.

The preparation and use of the active compounds according to theinvention can be seen from the following examples.

PREPARATIVE EXAMPLES: Example 1 ##STR17## Process (a)

2.5 g (25 mmol) of sec-butyl isocyanate are added to a mixture of 4.6 g(25 mmol) of 1-methyl-5-morpholino-1,2-dihydro-3H-1,2,4-triazol-3-oneand 150 ml of acetonitrile and after the addition of 2 drops of1,8-diazabicyclo-[5.4.0]-undec-7-ene (DBU), the reaction mixture isstirred at the reflux temperature for 2 hours. After cooling, thereaction mixture is filtered off under suction and the solid product isrecrystallized from hexane/ethyl acetate (1:1 by vol.).

This gives 4.4 g (62 % of theory) of2-(secbutyl-aminocarbonyl)-1-methyl-5-morpholino-1,2-dihydro-3H-1,2,4-triazol-3-onehaving a melting point of 147° C.

¹ -NMR (CDCl₃, δ, ppm): 1.15-1.25; 3.35; 7.95-8.00.

EXAMPLE 2 ##STR18## Process (b)

To a mixture of 7.8 g (38 mmol) of2-chlorocarbonyl-5-dimethylamino-1-methyl-1,2-dihydro-3H-1,2,4-triazol-3-oneand 150 ml of acetonitrile are added dropwise with stirring 9.2 g (75mmol) of 1-phenylethylamine so that the reaction temperature does notexceed 40° C. The reaction mixture is then stirred at 20° C. for 2 hoursand then filtered. The filtrate is concentrated under water pump vacuum,the residue is shaken with methylene chloride/water and the organicphase is dried using sodium sulphate and filtered. The filtrate is freedfrom solvent by distillation under water pump vacuum and the solidresidue is recrystallized from hexane/ethyl acetate (4:1 by vol.).

This gives 3.83 g (35 % of theory) of5-dimethylamino-1-methyl-2-(1-phenyl-ethylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one having a melting point of 103° C.

¹ H-NMR (CDCl₃, δ, ppm): 1.50-1.55; 3.15; 3.30; 7.20-7.35; 8.50-8.60.

Similarly to Examples 1 and 2 and corresponding to the generaldescription of the preparative process according to the invention, it isalso possible to prepare, for example, the compounds of the formula (I)listed in Table 1 which follows: ##STR19##

                                      TABLE 1                                     __________________________________________________________________________    Examples of compounds of the formula (I)                                       No.Ex.                                                                                       R.sup.3                                                                          R.sup.4       R.sup.5                                                                              X                                                                               or .sup.1 H-NMRpoint                                                         (°C.)Melting                  __________________________________________________________________________     3 N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR20##    CH.sub.3                                                                             O 131                                   4 N(CH.sub.3).sub.2                                                                         H  (CH.sub.2).sub.3CH.sub.3                                                                    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) :                                                         0.90-0.95;                                                                    3.15; 3.35                            5 N(CH.sub.3).sub.2                                                                         H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O 77                                    6 N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR21##    CH.sub.3                                                                             O 207                                   7 N(C.sub.2 H.sub.5).sub.2                                                                  H  CH(CH.sub.3 ).sub.2                                                                         CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) :                                                         1.20-1.25;                                                                    1.25-1.30;                                                                    3.30;                                                                         3.45-3.55;                                                                    3.95-4.05                             8                                                                                ##STR22##  H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 133                                   9 N(CH.sub.3).sub.2                                                                         H  C(CH.sub.3).sub.2 CH.sub.2 Cl                                                               CH.sub.3                                                                             O 135                                   10                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR23##    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.15-1.20;                                              .50-1.60; 3.15; 3.35; 3.75-3.85       11                                                                              N(CH.sub.3).sub.2                                                                         H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 63                                    12                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR24##    CH.sub.3                                                                             O 82                                    13                                                                              N(CH.sub.3).sub.2                                                                         H  C(CH.sub.3).sub.2 CH.sub.2 F                                                                CH.sub.3                                                                             O 110                                   14                                                                              N(CH.sub.3).sub.2                                                                         H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 135                                   15                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR25##    CH.sub.3                                                                             O 158                                   16                                                                              N(C.sub.2 H.sub.5).sub.2                                                                  H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 108                                   17                                                                              N(C.sub.2 H.sub.5).sub.2                                                                  H  C(CH.sub.3).sub.2 CH.sub.2 Cl                                                               CH.sub.3                                                                             O 82                                    18                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR26##    CH.sub.3                                                                             O 140                                   19                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.2 CHCH.sub.2                                                                         CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) :                                                         3.15; 3.35;                                                                   3.90-3.95;                                                                    5.70-5.95;                                                                    8.25-8.30                             20                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.2 CH.sub.2 CH.sub.3                                                                  CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) :                                                         0.90-1.00;                                                                    1.55-1.65;                                                                    3.15; 3.35                             21                                                                             N(CH.sub.3).sub.2                                                                         H  C.sub.2 H.sub.5                                                                             CH.sub.3                                                                             O 81                                    22                                                                              N(CH.sub.3).sub.2                                                                         H  CH(C.sub.2 H.sub.5).sub.2                                                                   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) :                                                         0.90-1.00;                                                                    1.40-1.65;                                                                    3.15; 3.35                            23                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.2 CH.sub.2 Cl                                                                        CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) :                                                         3.15; 3.35;                                                                   3.65                                  24                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR27##    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-0.95;                                              .15-1.20; 1.70-1.85; 3.15; 3.35       25                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR28##    CH.sub.3                                                                             O 127                                   26                                                                              N(C.sub.2 H.sub.5).sub.2                                                                  H                                                                                 ##STR29##    CH.sub.3                                                                             O 105                                   27                                                                              N(C.sub.2 H.sub.5).sub.2                                                                  H                                                                                 ##STR30##    CH.sub.3                                                                             O 107                                   28                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR31##    CH.sub.3                                                                             O 99                                    29                                                                              N(CH.sub.3).sub.2                                                                         H  C(CH.sub.3).sub.2 CHCl.sub.2                                                                CH.sub.3                                                                             O 93                                    30                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR32##    CH.sub.3                                                                             O 109                                   31                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR33##    CH.sub.3                                                                             O 172                                   32                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR34##    CH.sub.3                                                                             O 143                                   33                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR35##    CH.sub.3                                                                             O 177                                   34                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR36##    CH.sub.3                                                                             O 109                                   35                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR37##    CH.sub.3                                                                             O 76                                    36                                                                               ##STR38##  H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 148                                   37                                                                               ##STR39##  H                                                                                 ##STR40##    CH.sub.3                                                                             O 165                                   38                                                                               ##STR41##  H                                                                                 ##STR42##    CH.sub.3                                                                             O 225                                   39                                                                              N[CH(CH.sub.3).sub.2 ].sub.2                                                              H                                                                                 ##STR43##    CH.sub.3                                                                             O 124                                   40                                                                              N[CH(CH.sub.3).sub.2 ].sub.2                                                              H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 140                                   41                                                                              N[CH(CH.sub.3).sub.2 ].sub.2                                                              H                                                                                 ##STR44##    CH.sub.3                                                                             O 166                                   42                                                                              N[CH(CH.sub.3).sub.2 ].sub.2                                                              H                                                                                 ##STR45##    CH.sub.3                                                                             O 172                                   43                                                                               ##STR46##  CH.sub.3                                                                         CH.sub.3      CH.sub.3                                                                             O 138                                   44                                                                               ##STR47##  H                                                                                 ##STR48##    CH.sub.3                                                                             O 191                                   45                                                                               ##STR49##  H                                                                                 ##STR50##    CH.sub.3                                                                             O 177                                   46                                                                               ##STR51##  H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 121                                   47                                                                               ##STR52##  H                                                                                 ##STR53##    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-0.95;                                              .18-1.22; 2.00-2.05; 3.35;                                                    3.60-3.65                             48                                                                               ##STR54##  H                                                                                 ##STR55##    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.18-1.22;                                              .15-1.20; 3.20; 3.55-3.60;                                                    3.75-3.90                             49                                                                               ##STR56##  H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 112                                   50                                                                               ##STR57##  H                                                                                 ##STR58##    CH.sub.3                                                                             O 120                                   51                                                                               ##STR59##  H                                                                                 ##STR60##    CH.sub.3                                                                             O 84                                    52                                                                               ##STR61##  H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 83                                    53                                                                               ##STR62##  H                                                                                 ##STR63##    CH.sub.3                                                                             O 126                                   54                                                                               ##STR64##  H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.20-1.23;                                              .25-1.30; 3.1; 3.3; 3.50-3.60;                                                3.95-4.05                             55                                                                               ##STR65##  H  C(CH.sub.3).sub.2 CH.sub.2 F                                                                CH.sub.3                                                                             O 77                                    56                                                                              N(CH.sub.3).sub.2                                                                         H  C(CH.sub.3).sub.2 C CH                                                                      CH.sub.3                                                                             O 163                                   57                                                                               ##STR66##  H                                                                                 ##STR67##    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.18-1.22;                                              .25-1.30; 1.50-1.60; 3.15; 3.35       58                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR68##    CH.sub.3                                                                             O 115                                   59                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR69##    CH.sub.3                                                                             O                                       60                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR70##    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-1.80;                                              .15; 3.35                             61                                                                               ##STR71##  H                                                                                 ##STR72##    CH.sub.3                                                                             O 183                                   62                                                                              N[CH(CH.sub.3).sub.2 ].sub.2                                                              H                                                                                 ##STR73##    CH.sub.3                                                                             O 192                                   63                                                                               ##STR74##  H                                                                                 ##STR75##    CH.sub.3                                                                             O 192                                   64                                                                               ##STR76##  H                                                                                 ##STR77##    CH.sub.3                                                                             O 182                                   65                                                                               ##STR78##  H                                                                                 ##STR79##    CH.sub.3                                                                             O 169                                   66                                                                               ##STR80##  H                                                                                 ##STR81##    CH.sub.3                                                                             O 150                                   67                                                                               ##STR82##  H                                                                                 ##STR83##    CH.sub.3                                                                             O 159                                   68                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.3      CH.sub.3                                                                             S 103                                   69                                                                               ##STR84##  H  CH.sub.3      CH.sub.3                                                                             S (amorphous)                           70                                                                               ##STR85##  H  C.sub.2 H.sub.5                                                                             CH.sub.3                                                                             S 83                                    71                                                                               ##STR86##  H  C(CH.sub.3).sub.3                                                                           CH.sub.3                                                                             O 132                                   72                                                                               ##STR87##  H                                                                                 ##STR88##    CH.sub.3                                                                             O 94                                    73                                                                               ##STR89##  H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 172                                   74                                                                               ##STR90##  H  C(CH.sub.3).sub.2 CH.sub.2 F                                                                CH.sub.3                                                                             O 159                                   75                                                                               ##STR91##  H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O 152                                   76                                                                               ##STR92##  H                                                                                 ##STR93##    CH.sub.3                                                                             O 132                                   77                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR94##    CH.sub.3                                                                             O 62                                    78                                                                               ##STR95##  H                                                                                 ##STR96##    CH.sub.3                                                                             O 99                                    79                                                                               ##STR97##  H                                                                                 ##STR98##    CH.sub.3                                                                             O 125                                   80                                                                               ##STR99##  CH.sub.3                                                                         CH.sub.3      CH.sub.3                                                                             O 130                                   81                                                                               ##STR100## H                                                                                 ##STR101##   CH.sub.3                                                                             S 136                                   82                                                                               ##STR102## H  CH.sub.3      CH.sub.3                                                                             S 114                                   83                                                                               ##STR103## H  CH(C.sub.2 H.sub.5).sub.2                                                                   CH.sub.3                                                                             O (amorphous)                           84                                                                               ##STR104## H                                                                                 ##STR105##   CH.sub.3                                                                             O (amorphous)                           85                                                                               ##STR106## H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O (amorphous)                           86                                                                               ##STR107## H                                                                                 ##STR108##   CH.sub.3                                                                             O 117                                   87                                                                               ##STR109## H                                                                                 ##STR110##   CH.sub.3                                                                             O 113                                   88                                                                               ##STR111## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 88                                    89                                                                               ##STR112## H                                                                                 ##STR113##   CH.sub.3                                                                             O (amorphous)                           90                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.2 CH(CH.sub.3).sub.2                                                                 CH.sub.3                                                                             O (amorphous)                           91                                                                               ##STR114## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.15-1.25;                                              .35; 3.95-4.05                        92                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR115##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.85-0.90;                                              .80-1.90; 1.55-1.80; 3.15; 3.35       93                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR116##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.20-1.25;                                              .15; 3.35; 4.05-4.15                  94                                                                               ##STR117## H                                                                                 ##STR118##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.20-1.25;                                              .30; 3.35-3.40; 4.05-4.15             95                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR119##   CH(CH.sub.3).sub.2                                                                   O 118° C.                        96                                                                              N(CH.sub.3).sub.2                                                                         H  CH(CH.sub.3).sub.2                                                                          CH(CH.sub.3).sub.2                                                                   O 83° C.                         97                                                                               ##STR120## H                                                                                 ##STR121##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.14-1.17;                                              .10; 3.32 3.70-3.82; 8.05-8.10        98                                                                               ##STR122## H                                                                                 ##STR123##   CH.sub.3                                                                             O 97° C.                         99                                                                               ##STR124## H                                                                                 ##STR125##   CH.sub.3                                                                             O 97° C.                        100                                                                               ##STR126## H                                                                                 ##STR127##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-0.92;                                              .10; 3.30 3.55-3.63;                 101                                                                               ##STR128## H                                                                                 ##STR129##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-0.96;                                              .10; 3.30 3.50-3.56;                 102                                                                               ##STR130## H                                                                                 ##STR131##   CH.sub.3                                                                             O 54° C.                        103                                                                               ##STR132## H                                                                                 ##STR133##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.20-1.30;                                              .10; 3.32 3.37; 3.49-3.56            104                                                                               ##STR134## H                                                                                 ##STR135##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-0.95;                                              .14-1.16 1.25-1.30; 3.50-3.55        105                                                                               ##STR136## H  CH.sub.2C(CH.sub.3).sub.3                                                                   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) 0.95; 1.25-                                               1.30; 3.12; 3.32; 3.50- 3.60         106                                                                               ##STR137## H  CH.sub.2CH.sub.2CH.sub.3                                                                    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) 0.92-0.98;                                                3.12; 3.32 3.50-3.60                 107                                                                               ##STR138## H                                                                                 ##STR139##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.25-1.30;                                              .32-1.35 3.05-3.10; 3.60-3.65        108                                                                               ##STR140## H                                                                                 ##STR141##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.95;                                                   1.12- 1.15; 1.25- 1.30; 3.12;                                                 3.32; 3.70- 3.80                     109                                                                               ##STR142## H  (CH.sub.2).sub.3CH.sub.3                                                                    CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 0.90-0.96;                                              .33-1.60; 3.12; 3.25-3.30; 3.32      110                                                                               ##STR143## H                                                                                 ##STR144##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) 1.25-1.30;                                                3.12; 3.13-3.15; 3.32; 3.50-3.56                                              6                                    111                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR145##   CH.sub.3                                                                             O 115° C.                       112                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR146##   CH(CH.sub.3).sub.2                                                                   O 50° C.                        113                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR147##   CH(CH.sub.3).sub.2                                                                   O 118° C.                       114                                                                              N(CH.sub.3).sub.2                                                                         H  CH(CH.sub.3).sub.2                                                                          CH(CH.sub.3).sub.2                                                                   O 83° C.                        115                                                                              N(CH.sub.3).sub.2                                                                         H  C(CH.sub.3).sub.2 CH.sub.2 Cl                                                               CH(CH.sub.3).sub.2                                                                   O 81° C.                        116                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR148##                                                                                  ##STR149##                                                                          O 86° C.                        117                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.2CH(CH.sub.3).sub.2                                                                  C.sub.2 H.sub.5                                                                      O .sup.1 H-NMR*.sup.)                                                           0.95-0.98;                                                                    0.99-1.05;                                                                    1.78-1.90;                                                                    3.12-3.15;                                                                    3.18; 3.85-                                                                   3.92                                 118                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR150##   C.sub.2 H.sub.5                                                                      O .sup.1 H-NMR*.sup.) 0.90-1.05;                                                1.18-1.22; 1.50-1.60; 3.18;                                                   3.80- 3.90                           119                                                                              N(CH.sub.3 ).sub.2                                                                        H                                                                                 ##STR151##   C.sub.2 H.sub.5                                                                      O (amorphous)                          120                                                                              N(CH.sub.3).sub.2                                                                         H  CH(CH.sub.3).sub.2                                                                          C.sub.2 H.sub.5                                                                      O 52° C.                        121                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR152##                                                                                  ##STR153##                                                                          O 123° C.                       122                                                                              N(CH.sub.3).sub.2                                                                         H  CH(CH.sub.3).sub.2                                                                           ##STR154##                                                                          O 115° C.                       123                                                                               ##STR155## H                                                                                 ##STR156##   CH(CH.sub.3).sub.2                                                                   O .sup.1 H-NMR*.sup.) : 3.12;                                                   3.50- 3.60; 3.75- 3.85; 7.85-                                                 7.90                                 124                                                                               ##STR157## H  CH(CH.sub.3).sub.2                                                                          CH(CH.sub.3).sub.2                                                                   O .sup.1 H-NMR*.sup.) : 1.20-1.25;                                              .12; 3.50- 3.60; 3.75- 3.85;                                                  3.95- 4.05; 7.89- 7.92               125                                                                               ##STR158## H                                                                                 ##STR159##   CH.sub.3                                                                             O 75° C.                        126                                                                               ##STR160## H                                                                                 ##STR161##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 3.15; 3.30                                              .40-3.50; 3.60-3.75;                 127                                                                               ##STR162## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 155° C.                       128                                                                               ##STR163## H                                                                                 ##STR164##   CH.sub.3                                                                             O .sup.1 H-NMR*.sup.) : 1.40-1.45;                                              .12; 3.30 3.40-3.50; 3.75-3.90       129                                                                               ##STR165## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 62° C.                        130                                                                               ##STR166## H                                                                                 ##STR167##   CH.sub.3                                                                             O 63° C.                        131                                                                               ##STR168## H                                                                                 ##STR169##   C.sub.2 H.sub.5                                                                      O 72° C.                        132                                                                              N(CH.sub.3).sub.2                                                                         H  CH.sub.2 CH(CH.sub.3).sub.2                                                                  ##STR170##                                                                          O .sup.1 H-NMR*.sup.) : 0.90-0.95;                                              .10-1.90; 3.08-3.12; 3.15            133                                                                              N(CH.sub.3).sub.2                                                                         H                                                                                 ##STR171##                                                                                  ##STR172##                                                                          O 115° C.                       134                                                                               ##STR173## H                                                                                 ##STR174##   C.sub.2 H.sub.5                                                                      O 108° C.                       135                                                                               ##STR175## H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O (amorphous)                          136                                                                               ##STR176## H  CH(C.sub.2 H.sub.5).sub.2                                                                   CH.sub.3                                                                             O (amorphous)                          137                                                                               ##STR177## H                                                                                 ##STR178##   CH.sub.3                                                                             O 100° C.                       138                                                                               ##STR179## H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O (amorphous)                          139                                                                               ##STR180## H  CH(C.sub.2 H.sub.5).sub.2                                                                   CH.sub.3                                                                             O 95° C.                        140                                                                               ##STR181## H                                                                                 ##STR182##   CH.sub.3                                                                             O 85° C.                        141                                                                               ##STR183## H                                                                                 ##STR184##   CH(CH.sub.3).sub.2                                                                   O 125° C.                       142                                                                               ##STR185## H                                                                                 ##STR186##   CH.sub.3 (amorphous)                          143                                                                               ##STR187## H                                                                                 ##STR188##   CH.sub.3 (amorphous)                          144                                                                               ##STR189## H                                                                                 ##STR190##   CH.sub.3 (amorphous)                          145                                                                               ##STR191## H                                                                                 ##STR192##   CH.sub.3                                                                             O (amorphous)                          146                                                                               ##STR193## H                                                                                 ##STR194##   CH.sub.3                                                                             O (amorphous)                          147                                                                               ##STR195## H                                                                                 ##STR196##   CH.sub.3                                                                             O (amorphous)                          148                                                                               ##STR197## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O (amorphous)                          149                                                                               ##STR198## H                                                                                 ##STR199##   CH.sub.3                                                                             O (amorphous)                          150                                                                               ##STR200## H                                                                                 ##STR201##   CH.sub.3                                                                             O (amorphous)                          151                                                                               ##STR202## H                                                                                 ##STR203##   CH.sub.3                                                                             O (amorphous)                          152                                                                               ##STR204## H                                                                                 ##STR205##   CH.sub.3                                                                             O (amorphous)                          153                                                                               ##STR206## H                                                                                 ##STR207##   CH.sub.3                                                                             O 116° C.                       154                                                                               ##STR208## H                                                                                 ##STR209##   CH.sub.3                                                                             O (amorphous)                          155                                                                               ##STR210## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O (amorphous)                          156                                                                               ##STR211## H                                                                                 ##STR212##   CH.sub.3                                                                             O (amorphous)                          157                                                                               ##STR213## H                                                                                 ##STR214##   CH.sub.3                                                                             O (amorphous)                          158                                                                               ##STR215## H                                                                                 ##STR216##   CH.sub.3                                                                             O (amorphous)                          159                                                                               ##STR217## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 80° C.                        160                                                                               ##STR218## H  CH(C.sub.2 H.sub.5).sub.2                                                                   CH.sub.3                                                                             O (amorphous)                          161                                                                               ##STR219## H                                                                                 ##STR220##   CH.sub.3 (amorphous)                          162                                                                               ##STR221## H  CH(C.sub.2 H.sub.5 ).sub.2                                                                  CH.sub.3                                                                             O (amorphous)                          163                                                                               ##STR222## H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O (amorphous)                          164                                                                               ##STR223## H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O (amorphous)                          165                                                                               ##STR224## H                                                                                 ##STR225##   CH.sub.3                                                                             O (amorphous)                          166                                                                               ##STR226## H                                                                                 ##STR227##   CH.sub.3                                                                             O (amorphous)                          167                                                                               ##STR228## H  CH.sub.2 C(CH.sub.3).sub.3                                                                  CH.sub.3                                                                             O (amorphous)                          168                                                                               ##STR229## H  CH.sub.2 CH(CH.sub.3).sub.2                                                                 CH.sub.3                                                                             O (amorphous)                          169                                                                               ##STR230## H                                                                                 ##STR231##   CH.sub.3                                                                             O 72° C.                        170                                                                               ##STR232## H                                                                                 ##STR233##   CH.sub.3                                                                             O 101° C.                       171                                                                               ##STR234## H  CH.sub.2 C(CH.sub.3)                                                                        CH.sub.3                                                                             O 106° C.                       172                                                                               ##STR235## H  CH(CH.sub.3).sub.2                                                                          CH.sub.3                                                                             O 87° C.                        173                                                                               ##STR236## H                                                                                 ##STR237##   CH.sub.3                                                                             O 103° C.                       174                                                                               ##STR238## H                                                                                 ##STR239##   CH.sub.3                                                                             O 93° C.                        175                                                                               ##STR240## H                                                                                 ##STR241##   CH.sub.3                                                                             O (amorphous)                          176                                                                               ##STR242## H                                                                                 ##STR243##   CH.sub.3                                                                             O (amorphous)                          177                                                                               ##STR244## H                                                                                 ##STR245##   CH.sub.3                                                                             O 149° C.                       178                                                                               ##STR246## H                                                                                 ##STR247##   CH.sub.3                                                                             O (amorphous)                          179                                                                               ##STR248## H  CH.sub.2 CH(CH.sub.3).sub.2                                                                 CH.sub.3                                                                             O (amorphous)                          180                                                                               ##STR249## H                                                                                 ##STR250##   CH.sub.3                                                                             O (amorphous)                          __________________________________________________________________________     *.sup.) The .sup.1 HNMR spectra were recorded from solutions in CDCl.sub.     using tetramethylsilane (TMS) as internal standard. The chemical shift is     given by the δ value in ppm.                                       

STARTING MATERIALS OF THE FORMULA (II): Example (II-1) ##STR251## 1stStep: ##STR252##

A mixture of 35 g (0.5 mol) of dimethylcyanamide and 156 g (1.0 mol) ofphenyl chloroformate is stirred for 16 hours at 100° C. Then the morereadily volatile components are distilled off under water pump vacuum(bath temperature 80° C.) and the oily residue is distilled under oilpump vacuum.

This gives 61.4 g (54 % of theory) ofN,N-dimethyl-N'-phenoxycarbonyl-chloroformamidine having a boiling rangeof 158° C.-165° C./0.5mbar -0.8 mbar.

2nd Step: ##STR253##

A solution of 6.9 g (0.15 mol) of methylhydrazine in 100 ml of dioxaneis added dropwise with stirring at 20° C. to 30° C. (cooling necessary:)to a mixture of 17.0 g (0.075 mol) ofN,N-dimethyl-N,-phenoxycarbonyl-chloroformamidine and 100 ml ofmethylene chloride. The reaction mixture is stirred for 4 hours at 20°C. and then filtered off under suction. The filtrate is freed of solventby distillation under water pump vacuum and the liberated phenol isdistilled off under oil pump vacuum.

This gives 9.8 g (92 % of theory) of5-dimethylamino-1-methyl-1,2-dihydro-3H-1,2,4-triazol -3-one in the formof an oily residue.

¹ H-NMR (DMSO-d6, δ, ppm): 3.20; 3.45.

The product can be crystallized by boiling with acetonitrile; meltingpoint 222° C.

Example (II-2) ##STR254## 1st Step: ##STR255##

73 g (0.5 mol) of ethyl 2-isopropylhydrazinecarboxylate and 42 g (0.5mol) of sodium hydrogencarbonate are introduced into 200 ml of methylenechloride and 400 ml of water. 55 g (0.52 mol) of bromocyanogen areintroduced with stirring at room temperature (cooling necessary). Aftersubsequent stirring for three hours, the evolution of CO₂ has ceased.The organic phase is separated off in a separating funnel, dried oversodium sulphate and concentrated in a rotary evaporator.

This gives a residue of 73 g (85.4 % of theory) of ethyl2-isopropyl-2-cyanohydrazinecarboxylate in the form of a light oil.

¹ H-NMR: (CDCl₃, δ, ppm): 1.25-1.30; 1.30-1.35; 3.5-3.65; 4.20-4.30.

2nd Step: ##STR256##

To a solution of 100 ml of 33 % strength dimethylamine in absoluteethanol are added dropwise 35 g (0.2 mol) of ethyl2-isopropyl-2-cyano-hydrazinecarboxylate. The solution is first stirredfor 8 hours at room temperature and then for 1.5 hours at the refluxtemperature. Concentration in a rotary evaporator gives an oily residuewhich slowly crystallizes on standing. Recrystallization fromcyclohexane/ethyl acetate (4:1 by vol.) gives 30 g (88 % of theory) of5-dimethylamino-1-isopropyl-1,2-dihydro-3H-1,2,4-triazol -3-one having amelting point of 111° C.

A similar method can be used, for example, to prepare the compounds ofthe formula (II) listed in Table 2 which follows: ##STR257##

                  TABLE 2                                                         ______________________________________                                        Examples of the starting materials of the formula (II)                        Ex.                                Melting                                    No.     R.sup.1    R.sup.2    R.sup.5                                                                            point (°C.)                         ______________________________________                                        II-3    C.sub.2 H.sub.5                                                                          C.sub.2 H.sub.5                                                                          CH.sub.3                                                                            89                                        II-4    --CH.sub.2 CH.sub.2 --O--CH.sub.2 CH.sub.2 --                                                   CH.sub.3                                                                             183                                          II-5    --(CH.sub.2).sub.4 --                                                                           CH.sub.3                                                                             (amorph)                                     II-6    --(CH.sub.2).sub.5 --                                                                           CH.sub.3                                                                             (amorph)                                     II-7    CH(CH.sub.3).sub.2                                                                       CH(CH.sub.3).sub.2                                                                       CH.sub.3                                                                           119                                        II-8    CH.sub.3   C.sub.2 H.sub.5                                                                          CH.sub.3                                                                           (amorph)                                   II-9    CH.sub.3   CH.sub.3   C.sub.2 H.sub.5                                 ______________________________________                                    

STARTING MATERIALS OF THE FORMULA (IV): Example (IV-1) ##STR258##

A mixture of 14.2 g (0.1 mol) of5-methylamino-1-methyl-1,2-dihydro-3H-1,2,4-3-one and 200 ml ofacetonitrile is heated at the reflux temperature while introducingphosgene and phosgenated until hydrogen chloride evolution has ceased.Subsequently nitrogen is blown through the mixture and the solvent isthen carefully distilled off under water pump vacuum.

This gives 18.5 g (91 % of theory) of2-chlorocarbonyl-5-dimethylamino-1-methyl-1,2-dihydro-3H-1,2,4-triazol-3-onein the form of an oily residue which is used without furtherpurification or characterization for the next step according to process(b).

APPLICATION EXAMPLES Example A Pre-emergence test

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

Seeds of the test plants are sown in normal soil and, after 24 hours,watered with the preparation of the active compound. It is expedient tokeep constant the amount of water per unit area. The concentration ofthe active compound in the preparation is of no importance, only theamount of active compound applied per unit area being decisive. Afterthree weeks, the degree of damage to the plants is rated in % damage incomparison to the development of the untreated control. The figuresdenote:

0 %=no action (like untreated control)

100 %=total destruction

In this test, excellent herbicidal activity is shown by, for example,the compounds according to Preparative Examples 1, 5, 7, 9, 10, 11, 12,13, 14, 16, 20, 21, 22, 23, 24, 25, 32, 34, 49 and 54.

EXAMPLE B Post-emergence test

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To produce a suitable preparation of active compound, 1 part by weightof active compound is mixed with the stated amount of solvent, thestated amount of emulsifier is added and the concentrate is diluted withwater to the desired concentration.

Test plants which have a height of 5-15 cm are sprayed with thepreparation of the active compound in such a way as to apply theparticular amounts of active compound desired per unit area. Theconcentration of the spray liquor is chosen so that the particularamounts of active compound desired are applied in 2,000 1 of water/ha.After three weeks, the degree of damage to the plants is rated in %damage in comparison to the development of the untreated control. Thefigures denote:

0%=no action (like untreated control)

100%=total destruction

Excellent herbicidal activity and good to very good productive plantselectivity are shown in this test by, for example, the compoundsaccording to Preparative Examples 1, 2, 4, 5, 9, 10, 11, 12, 13, 14, 20,21, 22, 23, 24, 25, 26, 28, 29, 32, 34, 35 and 36.

It will be appreciated that the instant specification is set forth byway of illustration and not limitation, and that various modificationsand changes may be made without departing from the spirit and scope ofthe present invention.

What is claimed is:
 1. A substituted triazolinone of the formula ##STR259## in which R¹ and R², independently of one another, represent alkyl having 1 to 4 carbon atoms,R⁴ represents alkyl having 1 to 5 carbon atoms, halogenoalkyl having 1 to 4 carbon atoms, cycloalkyl having 3 to 8 carbon atoms, aralkyl having 6 to 10 carbon atoms in the aryl moiety and 1 to 6 carbon atoms in the alkyl moiety and optionally substituted on the aryl moiety by identical or different substituents selected from the group consisting of phenoxy, of cycloalkyl having 3 to 6 carbon atoms and optionally substituted by halogen or cyano, of halogen, cyano, nitro, hydroxyl and alkyl, alkoxy, alkylthio, halogenoalkyl, halogenoalkoxy, halogenoalkylthio, alkylsulphinyl, alkylsulphonyl, halogenoalkylsulphinyl, halogenoalkylsulphonyl, alkanoyl and alkoxycarbonyl, each of which may be straight-chain or branched, each having 1 to 6 carbon atoms and up to 9 identical or different halogen atoms, and R⁵ represents straight-chain or branched alkyl having 1to 4 carbon atoms.
 2. A compound according to claim 1, wherein such compound is 5-dimethylamino-1-methyl-2-(1-phenyl-ethylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one of the formula ##STR260##
 3. A compound according to claim 1, wherein such compound is 5-dimethylamino-1-methyl-2-(chloro-t-butylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one of the formula ##STR261##
 4. A compound according to claim 1, wherein such compound is 5-dimethylamino-1-methyl-2-(cyclohexylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one of the formula ##STR262##
 5. A compound according to claim 1, wherein such compound is 5-dimethylamino-1-methyl-2-(t-butylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one of the formula ##STR263##
 6. A compound according to claim 1, wherein such compound is 5-dimethylamino-1-methyl-2-neopentylaminecarbonyl-1,2-dihydro-3H-1,2,4-triazol-3-one of the formula ##STR264##
 7. A herbicidal composition comprising a herbicidally effective amount of a compound according to claim 1 and a diluent.
 8. A method of combating unwanted vegetation which comprises administering to such vegetation or to a locus from which it is desired to exclude such vegetation a herbicidally effective amount of a compound according to claim
 1. 9. The method according to claim 8, wherein such compound is5-dimethylamino-1-methyl-2-(1-phenyl-ethylamino-carbonyl)1,2-dihydro-3H-1,2,4-triazol-3-one, 5-dimethylamino-1-methyl-2-(chloro-t-butylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one, 5-dimethylamino-1-methyl-2-(cyclohexylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one, 5-dimethylamino-1-methyl-2-(t-butylamino-carbonyl)-1,2-dihydro-3H-1,2,4-triazol-3-one, or 5-dimethylamino-1-methyl-2-neopentylamine-carbonyl-1,2-dihydro-3H-1,2,4-triazol-3-one. 